Income Taxes (Tables)

12 Months Ended

Dec. 31, 2019

Schedule of Domestic and Foreign Components of Loss before Provision for Income Taxes

For financial reporting purposes, the components of loss from continuing operations before income taxes were as follows (in thousands):


	December 31,
	2019		2018		2017
United States	$	(325,769)	$	(35,838)	$	(32,112)
Foreign	(93,734)		(87,878)		(93,910)
Total	$	(419,503)	$	(123,716)	$	(126,022)

Reconciliation of Income Tax to Expense (Benefit)

A reconciliation of income tax provision to amounts computed by applying the statutory federal income tax rate to loss from continuing operations before income taxes is shown as follows (in thousands):


	December 31,
	2019		2018		2017
Income tax at federal statutory rate	$	(88,096)	$	(26,022)	$	(42,846)
State taxes, net of federal benefit	(65)		(8)		(19)
Non-deductible acquired IPR&D charge and other expenses⁽¹⁾	52,044		—		—
Change in valuation allowance	21,155		16,949		(11,208)
Impact of U.S. statutory rate change on revaluing deferred tax assets	—		—		36,085
Impact of foreign rate change on deferred taxes	1,887		1,961		1,619
Other permanent differences	4,101		(701)		8,086
State tax rate benefit	(18)		169		56
Foreign rate differential	1,883		1,731		10,636
Stock-based compensation	(2,674)		(1,344)		(2,462)
Net operating losses surrendered under U.K.’s R&D tax relief scheme	9,349		6,322		—
Credits and other	434		943		53
Income tax provision	$	—	$	—	$	—

(1)Amounts attributable to our asset acquisition of Modis. See Note 3 for additional information.

Schedule of Deferred Tax Assets

The significant components of deferred tax assets (liabilities) were as follows (in thousands):


	December 31,
	2019		2018
Deferred tax assets:
Federal and state net operating loss carryforwards	$	134,009	$	103,187
Capitalized research and development	925		1,537
Accrued expenses	1,311		1,300
Research and development credits	5,343		5,343
Amortization	1028		528
Lease liability	2,547		—
Stock-based compensation	6,464		5,868
Other, net	1,979		775
Total deferred tax assets	153,606		118,538
Less: valuation allowance	(151,544)		(118,064)
Total deferred tax assets, net of valuation allowance	2,062		474

Deferred tax liabilities:
Operating lease right-of-use asset	$	(1,640)	$	—
IPR&D	(17,425)		(17,425)
Depreciation	(422)		(474)
Total deferred tax liabilities	(19,487)		(17,899)
Total net deferred tax liabilities	$	(17,425)	$	(17,425)

Summary of Unrecognized Tax Benefits

The following table summarizes the activity related to our unrecognized tax benefits (in thousands):


	December 31,
	2019		2018		2017
Beginning balance of unrecognized tax benefits	$	1,487	$	2,030	$	1,248
Gross increases based on tax positions related to current year	1,495		—		633
Gross increases based on tax positions related to prior years	559		91		149
Gross decreases based on tax positions related to prior years	—		(634)		—
Settlements with taxing authorities	—		—		—
Expiration of statute of limitations	—		—		—
Ending balance of unrecognized tax benefits	$	3,541	$	1,487	$	2,030